Add timer for git/upload-pack/phase_searching_for_*

JGit packer tracks time spent in searching for reuse and sizes
associated with the phase "Finding sources".

Gerrit already has an out-of-the-box capability for
tracking JGit protocol-level metrics, but did not cover until
now, the "Finding sources" phase, which is critical for an optimal
Git/HTTP performance.

Add the git/upload-pack/phase_searching_for_* so that the Gerrit
admin can graph how these are performing and spot any potential
issues.

Release-Notes: Add timer for git/upload-pack/phase_searching_for_* phases
Change-Id: I65abde2c2157de61f4ee2114609085065aa5a659

2 files changed, 28 insertions, 0 deletions

diff --git a/Documentation/metrics.txt b/Documentation/metrics.txt
index 2ed2c2e23b..396715fe24 100644
--- a/Documentation/metrics.txt
+++ b/Documentation/metrics.txt
@@ -377,6 +377,12 @@ Each queue provides the following metrics:
 * `git/upload-pack/phase_negotiating`: Time spent in the negotiation phase.
 ** `operation`:
    The name of the operation (CLONE, FETCH).
+* `git/upload-pack/phase_searching_for_reuse`: Time spent in the 'Finding sources...' while searching for reuse phase.
+** `operation`:
+   The name of the operation (CLONE, FETCH).
+* `git/upload-pack/phase_searching_for_sizes`: Time spent in the 'Finding sources...' while searching for sizes phase.
+** `operation`:
+   The name of the operation (CLONE, FETCH).
 * `git/upload-pack/phase_writing`: Time spent transferring bytes to client.
 ** `operation`:
    The name of the operation (CLONE, FETCH).
diff --git a/java/com/google/gerrit/server/git/UploadPackMetricsHook.java b/java/com/google/gerrit/server/git/UploadPackMetricsHook.java
index e1403828b9..9164dd36ed 100644
--- a/java/com/google/gerrit/server/git/UploadPackMetricsHook.java
+++ b/java/com/google/gerrit/server/git/UploadPackMetricsHook.java
@@ -40,6 +40,8 @@ public class UploadPackMetricsHook implements PostUploadHook {
   private final Timer1<Operation> counting;
   private final Timer1<Operation> compressing;
   private final Timer1<Operation> negotiating;
+  private final Timer1<Operation> searchingForReuse;
+  private final Timer1<Operation> searchingForSizes;
   private final Timer1<Operation> writing;
   private final Histogram1<Operation> packBytes;
 
@@ -81,6 +83,24 @@ public class UploadPackMetricsHook implements PostUploadHook {
                 .setUnit(Units.MILLISECONDS),
             operationField);
 
+    searchingForReuse =
+        metricMaker.newTimer(
+            "git/upload-pack/phase_searching_for_reuse",
+            new Description(
+                    "Time spent in the 'Finding sources...' while searching for reuse phase")
+                .setCumulative()
+                .setUnit(Units.MILLISECONDS),
+            operationField);
+
+    searchingForSizes =
+        metricMaker.newTimer(
+            "git/upload-pack/phase_searching_for_sizes",
+            new Description(
+                    "Time spent in the 'Finding sources...' while searching for sizes phase")
+                .setCumulative()
+                .setUnit(Units.MILLISECONDS),
+            operationField);
+
     writing =
         metricMaker.newTimer(
             "git/upload-pack/phase_writing",
@@ -109,6 +129,8 @@ public class UploadPackMetricsHook implements PostUploadHook {
     counting.record(op, stats.getTimeCounting(), MILLISECONDS);
     compressing.record(op, stats.getTimeCompressing(), MILLISECONDS);
     negotiating.record(op, stats.getTimeNegotiating(), MILLISECONDS);
+    searchingForReuse.record(op, stats.getTimeSearchingForReuse(), MILLISECONDS);
+    searchingForSizes.record(op, stats.getTimeSearchingForSizes(), MILLISECONDS);
     writing.record(op, stats.getTimeWriting(), MILLISECONDS);
     packBytes.record(op, stats.getTotalBytes());
   }